Routing flexible printed circuit board through hinge of electronic device

ABSTRACT

A hinge is configured for routing electrical wiring therein. The hinge includes a pair of opposing bosses aligned along a rotational axis and a hollow portion having ends respectively engaging the bosses. The hollow portion is rotatable about the rotational axis, relative to the bosses. Wiring, such as a flexible printed circuit board (FPCB) has a portion thereof inserted into the hollow portion. A rod is inserted into the hollow portion and aligned along the rotational axis. The rod fixes the inserted portion of the wiring in a neutral position, and thus, reduces wear and tear on the wiring caused by the hinge action.

TECHNICAL FIELD

The present invention generally relates to electronic devices, and moreparticularly, to electronic devices that include wiring that passesbetween hinged elements.

BACKGROUND

Many contemporary electronic devices include hinged components so thatthe devices can be folded in order to reduce their overall physicalsizes. Cellular “flip” phones and laptop computers are common examplesof such electronic devices.

In many cases, these hinged electronic devices include electronics thatare located within the housings on both sides of a hinge. Usually, theseelectronics are wired together with wires that are routed through andconcealed within the hinge. For example, many contemporary flip phoneshave an electronic display screen located on the top half of the phoneand a keypad located on the bottom half of the phone. The top and bottomhalves are connected together with a hinge that permits the phone to beopened and closed. In order to display numbers and letters that areentered using the keypad of the bottom half on the upper-half displayscreen, the keypad and the display screen are essentially connectedtogether by wiring that is concealed within the hinge.

Routing the wiring through a hinge presents certain technicaldifficulties and reliability issues.

SUMMARY

Repeatedly cycling of a hinged electronic device through opened andclosed positions can cause wear and tear to wiring routed within thehinge, thus, eventually causing the electronic device to stop operatingproperly. Wear and tear on the wiring is frequently caused by the wiringrubbing against the interior walls of the hinge. In addition, the hingeaction during opening and closing may also cause torsion, stretchingand/or skewing of the wiring within the hinge, which may lead tounreliable operation or failure of the electronic device. Manufacturingvariances may also make it difficult to consistently place conventionalwiring within the hinge so as to avoid the wear and tear effectsnormally associated with hinge action.

To overcome these problems, an improved hinge assembly is disclosed. Theassembly includes a hinge configured to route and conceal electricalwiring. The hinge includes a pair of opposing bosses aligned along arotational axis and a hollow portion having ends respectively engagingthe bosses. The hollow portion is rotatable about the rotational axis,relative to the bosses. Wiring, such as a flexible printed circuit board(FPCB), has a portion thereof inserted into the hollow portion. A rod isinserted into the hollow portion and aligned along the rotational axis.The rod fixes the inserted portion of the wiring in a neutral position,avoiding contact with the interior walls of the hinge, and thus, reduceswear and tear on the wiring caused by the hinge action. The rod alsokeeps the wiring from stretch and/or skewing inside the hinge. Theaddition of the rod into the interior of the hinge significantlyimproves the reliability of the electrical connection passing throughthe hinge.

Other aspects, features, advantages of the hinge assembly will be orwill become apparent to one with skill in the art upon examination ofthe following figures and detailed description. It is intended that allsuch additional aspects, features, and advantages be included withinthis description and be protected by the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

It is to be understood that the drawings are solely for purpose ofillustration and do not define the limits of what is claimed.Furthermore, the components in the figures are not necessarily to scale.In the figures, like reference numerals designate corresponding partsthroughout the different views.

FIG. 1 is a perspective view of an exemplary cellular flip phone 10 thatincludes a flexible printed circuit board routed through a hinge.

FIG. 2 is a plan view of the flexible printed circuit board included inthe phone shown in FIG. 1.

FIG. 3 is a cross-sectional view of the hinge assembly of the cellularphone show in FIG. 1.

FIG. 4 is a perspective view of the rotatable hollow portion of thehinge assembly with the flexible printed circuit board inserted.

FIG. 5A is a cross-sectional view of the insert portion of the flexibleprinted circuit board prior to attachment to the rod.

FIG. 5B is a cross-sectional view of the rotatable hollow portion alongsection A-A of FIG. 4, with the flexible printed circuit board attachedto the rod.

DETAILED DESCRIPTION

The following detailed description, which references to and incorporatesthe drawings, describes and illustrates one or more specific embodimentsof the invention. These embodiments, offered not to limit but only toexemplify and teach the invention, are shown and described in sufficientdetail to enable those skilled in the art to practice the invention.Thus, where appropriate to avoid obscuring the invention, thedescription may omit certain information known to those of skill in theart.

The word “exemplary” is used throughout this disclosure to mean “servingas an example, instance, or illustration.” Any embodiment or featuredescribed herein as “exemplary” is not necessarily to be construed aspreferred or advantageous over other embodiments or features.

FIG. 1 is a perspective view of an exemplary cellular flip phone 10 thatincludes a flexible printed circuit board (FPCB) routed through a hinge16. The phone 10 includes an upper half 12 connected to a lower half 14by the hinge 16. The halves 12, 14 each represent a hinged element. Eachhalf 12, 14 includes electronics that are wired together with one ormore wires that are routed through and concealed within the hinge 16.For example, phone 10 includes an electronic display screen 22, such asa liquid crystal display (LCD), located on the upper half 12 of thephone 101 and a microphone 24 and keypad (not shown) located on thelower half 14 of the phone 10. The keypad, display screen 22 and otherelectronic components not shown are essentially connected together bywiring that is concealed within the hinge 16.

The hinge 16 permits the phone 10 to be opened and closed. The hinge 16includes to a pair of opposing bosses 18, 20 aligned along a rotationalaxis of the hinge 59 (see FIGS. 2-3) and a hollow portion 21 having endsrespectively engaging the bosses 18, 20. The hollow portion 21 isrotatable about the rotational axis 59, relative to the bosses 18, 20.

The wiring running through the hinge 16 between electronic components inthe upper and lower halves 12, 14 may be any suitable conductor,including one or more individual wires, an FPCB having one or moreconductive traces, or the like. In the exemplary phone 10 describedherein, the wiring is an FPCB.

The bosses 18, 20 may be integrally formed as part of the lower halfhousing, and the rotatable hollow portion 21 may be integrally formed aspart of the upper half housing.

Although FIG. 1 shows a cellular phone 10, the hinge assembly 49described herein can be used in any electronic device having wiringrouted through a hinge that connects hinged components of the device.For example, the hinge 16 may be included in other wirelesscommunication devices, such as headsets, personal digital assistants(PDAs), smart phones, or the like, as well as other electronic devices,such as laptop or portable computers.

FIG. 2 is a plan view of the flexible printed circuit board (FPCB) 40included in the phone 10 shown in FIG. 1. The FPCB 40 includes an upperportion 45, a lower portion 43, and an insert portion 42 connecting theupper and lower portions, 45, 43. The lower portion 43 includes a headerconnector 44, and the upper portion 45 includes a second headerconnector, which is not shown in FIG. 2, as it is located on theopposite side of the upper portion 45, in this example.

The FPCB 40 acts as wiring between the header connectors. The headerconnectors are electrical connectors that connect, respectively, toelectrical components separately located in upper and lower halves 12,14 of the phone 10. The header connectors can be any suitable type ofconnector, including those that have a multitude of individual pins(e.g., 40 pins) for making a multitude of individual electrical contactswith the components. The FPBC 40 includes one or more traces forelectrically connecting the pins on the different header connectors. Thetraces are formed along the upper and lower portions 45, 43 and passbetween the two portions 45, 43 by way of the insert portion 42. Thetraces can be metallic layers formed on and/or within the FPCB 40.

The FPCB 40 can have any suitable number of layers for carrying thewiring, for example, six layers.

FIG. 3 is a cross-sectional view of the hinge assembly 49 of thecellular phone 10 show in FIG. 1. The assembly 49 includes the hinge 16configured to route and conceal electrical wiring (e.g., a portion ofFPCB 40). The hinge 16 includes the opposing bosses 18, 20 aligned alongthe rotational axis 59 and a hollow portion 50 having ends 57respectively engaging the bosses 18, 20. The hollow portion 50 isrotatable about the rotational axis 59, relative to the bosses 18, 20.The FPCB 40 has the insert portion 42 thereof inserted into the hollowportion 50.

A rod 52 is inserted into the hollow portion 50 and aligned along therotational axis 59. The rod 52 fixes the inserted portion 42 of the FPCB40 in a neutral position, avoiding contact with the interior walls ofthe hinge 16, and thus, reduces wear and tear on the FPCB 40 caused bythe hinge action. The rod also keeps the FPCB from stretch and/orskewing inside the hinge. The addition of the rod 52 into the interiorof the hinge 16 significantly improves the reliability of the electricalconnection passing through the hinge 16.

The hollow portion 50 of the hinge 16 is preferably acylindrically-shaped tube, but it may be implemented in other shapes.Each end 57 of the hollow portion 50 is necked down to form a reducedannular contact surface 58 for snuggly engaging corresponding annularreceptacles 56 formed in each boss 18, 20.

The left boss 18 can include an interior hollow cavity 54 for receivingand concealing a portion the FPCB 40. A slot (not shown) may be formedin the boss 18 so that the FPCB 40 can be slid edgewise into the cavity54.

The components 18, 20, 50, 52 of the hinge 16 made be made of anysuitable material, such as injection molded plastic or the like.Alternatively, the rod 52 made be made of metal. Although shown as acylinder, the rod 52 may have any other suitable shape.

FIG. 4 is a perspective view of the rotatable hollow portion 50 of thehinge assembly 49 with the flexible printed circuit board 40 inserted.The hollow portion 50 includes a slot 60 running lengthwise and formedcompletely through its wall so that the FPCB 40 can be slid into thehollow portion 50 edgewise at one of the ends 57.

To assemble the hinge assembly 49, the insert portion 42 of the FPCB 40is first free-formed (i.e., bent) into a shape that contours theexterior surface of the rod 52, as shown in FIG. 5A. FIG. 5A is across-sectional view of the insert portion 42 of the FPCB 40 prior toattachment to the rod 52. An adhesive is applied between the FPCB insertportion 42 and rod 52, preferably by applying it to a surface of theFPCB insert portion 42, and then the insert portion 42 is glued to therod 52, as shown in FIG. 5B. FIG. 5B is a cross-sectional view of thehollow portion 50 of the hinge 16 along section A-A of FIG. 4, with theinsert portion 42 attached to the rod 52.

After attaching the FPCB insert portion 42 to the rod 52, the rod 52 andthe insert portion 42 are slid into one end 57 of the hollow portion,with the FPCB edge aligned in the slot 60. The rod 52 is thenpress-fitted into the opening at the other end 57 of the hollow portion50, at the reduced annular end 58 of the hollow portion 50. The openingmay be sized to snuggly engage the rod 52. The assembled hollow portion50, as shown in FIG. 4, is then snap-fitted into the bosses 18, 20 byfirst sliding the exposed left part of the FPCB insert portion 42edgewise into the slot of the left boss 18 so that the exposed left partof the FPCB insert portion 42 is concealed in the interior cavity 54,and then snapping the right end 57 of the hollow portion 50 into thereceptacle 56 of right boss 20.

The left boss 18 may include in its interior an annular bearing surface(not shown) centered and orthogonally aligned with the rotational axis59 for receiving and snuggly engaging the inserted end of the rod 52.

Other embodiments and modifications of this invention will occur readilyto those of ordinary skill in the art in view of these teachings. Theabove description is illustrative and not restrictive. The invention isto be limited only by the following claims, which cover all such otherembodiments and modifications, when viewed in conjunction with the abovespecification and accompanying drawings. The scope of the inventionshould, therefore, not be limited to the above description, but insteadshould be determined with reference to the appended claims along withtheir full scope of equivalents.

1. A hinge having a rotational axis, comprising: a pair of opposingbosses aligned along the rotational axis; a hollow portion having endsrespectively engaging the bosses, the hollow portion rotatable about therotational axis; wiring having a portion thereof inserted into thehollow portion; and a rod inserted into the hollow portion and alignedalong the rotational axis.
 2. The hinge of claim 1, further comprising:an adhesive applied to the portion of the wiring inserted into thehollow portion.
 3. The hinge of claim 2, wherein the adhesive securesthe wiring to the rod.
 4. The hinge of claim 1, wherein the portion ofthe wiring inserted within the hollow portion is shaped to wrap aroundat least part of the exterior surface of the rod.
 5. The hinge of claim1, included in an electronic device.
 6. The hinge of claim 2, includedin a wireless communication device.
 7. The hinge of claim 1, wherein atleast one of the bosses includes an interior cavity and part of thewiring passes through the interior cavity.
 8. The hinge of claim 1,wherein the hollow portion includes a longitudinal slot.
 9. A wirelesscommunication device having hinged elements, comprising: a hingecoupling the hinged elements, the hinge including: a pair of opposingbosses aligned along a rotational axis of the hinge; a hollow portionhaving ends respectively engaging the bosses, the hollow portion beingrotatable about the rotational axis; a flexible printed circuit boardhaving a portion thereof inserted into the hollow portion of the hinge;and a rod inserted into the hollow portion and aligned along therotational axis.
 10. The wireless communication device of claim 9,wherein the opposing bosses are integrally formed into a first housingelement of the wireless communication device and the hollow portion isintegrally formed into a second housing element of the wirelesscommunication device.
 11. The wireless communication device of claim 9,wherein the flexible printed circuit board connects a plurality ofelectronic components located in a first hinged element and a secondhinged element.
 12. The wireless communication device of claim 9,further comprising: an adhesive applied to the portion of the flexiblecircuit board inserted into the hollow portion.
 13. The wirelesscommunication device of claim 12, wherein the adhesive secures theflexible printed circuit board to the rod.
 14. The wirelesscommunication device of claim 9, wherein the portion of the flexibleprinted circuit board inserted within the hollow portion is shaped towrap around at least part of the exterior surface of the rod.
 15. Thewireless communication device of claim 9, wherein the rod iscylindrical.
 16. A method for routing a flexible printed circuit boardthrough a hinge, comprising: securing a rod within a rotatable portionof the hinge; and inserting a portion of the flexible printed circuitboard into the rotatable portion of the hinge.
 17. The method of claim16, further comprising: applying an adhesive on a surface of theflexible printed circuit board; and securing the rod to the adhesive onthe flexible printed circuit board.
 18. The method of claim 16, furthercomprising: shaping the portion of the flexible printed circuit board towrap around at least part of the surface of the rod.
 19. The method ofclaim 16, wherein the hinge connects two elements in an electronicdevice.
 20. The method of claim 19, wherein the flexible printed circuitboard connects a plurality of components in the two elements.